还可以在类型为 ReportData 的变量的 connectionName 字段中使用该别名。
SysLib.defineDatabaseAlias( alias STRING in, database STRING in)
如果未指定连接,则函数将影响当前连接。
// Connect to a database with alias "alias", // which becomes the current connection. defineDatabaseAlias( "alias", "database" ); connect( "alias", "user", "pwd" ); // Make two connections to the same database. String db = "database"; defineDatabaseAlias( "alias1", db ); defineDatabaseAlias( "alias2", db ); connect( "alias1", "user", "pwd" ); connect( "alias2", "user", "pwd" ); // Another way to make two connections // to the same database. defineDatabaseAlias( "alias", "database" ); connect( "alias", "user", "pwd" ); connect( "database", "user", "pwd" ); // An alias is defined but not used. The second // connect() does not create a new connection. defineDatabaseAlias( "alias", "database" ); connect( "database", "user", "pwd" ); connect( "database", "user", "pwd" ); // Use of an alias (which is case-insensitive) // when disconnecting. defineDatabaseAlias( "alias", "database" ); connect( "aLiAs", "user", "pwd" ); disconnect( "ALIAS" ); // The next disconnect call fails because the // connection is called "alias" not "database". defineDatabaseAlias( "alias", "database" ); connect( "alias", "user", "pwd" ); disconnect( "database" ); // An alias may change. After the next call, // "alias" refers to "firstDatabase" defineDatabaseAlias( "alias", "firstDatabase" ); // After the next call, // "alias" refers to "secondDatabase". defineDatabaseAlias( "alias", "secondDatabase" ); // The last call would have failed // if a connection was in place with "alias".
相关概念
EGL 函数的语法图
SQL 支持